Inflammatory:
– Acute appendicitis and periappendicitis
– Appendiceal diverticulum
– Non-necrotizing granulomatous inflammation (see comment)
COMMENT: The appendix shows scattered nonnecrotizing granulomas. Such granulomatous appendicitis can be seen in a variety of settings including both infectious and noninfectious etiologies. Special stains for mycobacteria and fungi have been ordered and will be reported in an addendum. Granulomas can also be seen in certain bacterial infections, notably Yersinia infection. Granulomas can also be seen with sarcoidosis, in response to a foreign body (including stool contents), after delayed appendectomy, and in Crohn’s disease. In this particular case, there are no additional findings to suggest the diagnosis of Crohn’s disease. Clinical correlation is recommended.
Tumors:
– Hyperplastic polyp
– Sessile serrated lesion
(with or without dysplasia)
– Low-grade appendiceal mucinous neoplasm (LAMN)
– High-grade appendiceal mucinous neoplasm (HAMN)
– Adenocarcinoma, *** differentiated
– Mucinous adenocarcinoma
– Signet-ring cell adenocarcinoma
– Appendiceal goblet cell adenocarcinoma, *** grade
COMMENT: Histologic sections of the appendix show an appendiceal goblet cell adenocarcinoma. These tumors were previously referred to as “goblet cell carcinoids” and spectrum of similar/related terms, however, they have been renamed to reflect their behavior more akin to glandular neoplasms than neuroendocrine neoplasms. This particular tumor shows approximately ***% tubular/clustered growth (low-grade pattern) and ***% high-grade growth (including sheet-like growth and single-cell infiltration). Please see the synoptic checklist below for additional information.
Last updated: May 5, 2019